Establecimiento de cuatro especies de Quercus en el sur de la ...

Reforestation with Quercus ilex L. and Q. suber L. by direct seeding and planting in southern Spain
ABSTRACT
The limited ability of Quercus species to regenerate naturally in Mediterranean
forests has led to the development of various reforestation techniques; however,
there is no general consensus as to what specific technique is the best for this purpose.
In this work, we assessed growth and survival in two Quercus species (Q. ilex ssp
ballota and Q. suber) used for reforestation in two different afforestation techniques
(viz. direct seeding and planting) and two seedling quality (1‐year‐old seedlings and 3‐
year‐old seedlings) in southern Spain. One‐year‐old seedlings of both species were
found to exhibit the highest survival rates and direct‐seeded plants intermediate
survival values. Also, seed mass was found to have a significantly positive effect on
establishment success in both species. No clear‐cut trend in survival, however, was
detected in 3‐year‐old seedlings. Survival in 3‐year‐old Q. suber seedlings and directseeded
plants was similar, but not in Q. ilex, where 3‐year‐old seedlings survived less.
The latter result may have been a consequence of cultivation in smaller containers
leading to root deformation and limiting plant access to water. Differences in survival
could not be ascribed to growth variables or stomatal conductance. Based on the
results, all three afforestation methods can be similarly effective provided appropriate
nursery cultivation conditions are used and seeds are protected against predators, the
best choice in each case being dictated by the particular restoration goals.
Keywords: direct seeding, planting, stomatal conductance, survival
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